Pump sizing

boxxmann · 05/04/2016, 06:53 AM

I currently have a 92 gallon corner mixed reef tank. My return pump is a Mag 7 pump. Is this enough, or should I go with a bigger pump? My original pump is toast and this is all that I had laying around. If this is sufficient, I might as well keep it instead of buying another pump. I was using a Mag 9.5. Thanks.

GimpyFin · 05/04/2016, 08:48 AM

You really only need about 3-5× tank volume for flow per hour on the return, so a mag 7 would be more than adequate at 700 gph.

mfinn · 05/04/2016, 09:19 AM

Quote:

Originally Posted by boxxmann

I currently have a 92 gallon corner mixed reef tank. My return pump is a Mag 7 pump. Is this enough, or should I go with a bigger pump? My original pump is toast and this is all that I had laying around. If this is sufficient, I might as well keep it instead of buying another pump. I was using a Mag 9.5. Thanks.

IMO it will be just fine for return pump flow.

boxxmann · 05/04/2016, 10:45 AM

So, what am I actually circulating? I probably have about a 4 foot head from the pump to the tank. Is that still adequate? I also have 2 powerheads in the main tank. Does that matter?

GimpyFin · 05/04/2016, 11:18 AM

This is just the flow through the sump with the return pump. The flow inside the tank with power heads is separate. I don't know the head loss with a mag 7, but even if you had 50% head loss (Which seems unlikely), you'd still be 350 gph which is between 3-4x tank volume, and perfectly fine.

boxxmann · 05/04/2016, 11:33 AM

Thanks. I hope you are right. I am just a bit afraid because I have had the 9.5 on it for a while and it just crapped out on me this morning.

mfinn · 05/04/2016, 12:01 PM

Quote:

Originally Posted by boxxmann

Thanks. I hope you are right. I am just a bit afraid because I have had the 9.5 on it for a while and it just crapped out on me this morning.

you will be fine.
The difference is only about 250 gallons per hour flow.
It will probably a little quieter. A little smaller pump, less water noise.

boxxmann · 05/04/2016, 12:04 PM

it actually is a little quieter, but still have the same ol" drain noise

Potatohead · 05/04/2016, 02:53 PM

Before you were running about eight times an hour through your sump, which is fine, but it's a bit on the high side. Now you're more like around 5 which is great.

Romanov · 05/17/2016, 06:20 PM

I am running it at 6 times the volume of the tank and seems ok for me

05/04/2016, 06:53 AM	#1
boxxmann Registered Member Join Date: Jun 2007 Posts: 138	Pump sizing I currently have a 92 gallon corner mixed reef tank. My return pump is a Mag 7 pump. Is this enough, or should I go with a bigger pump? My original pump is toast and this is all that I had laying around. If this is sufficient, I might as well keep it instead of buying another pump. I was using a Mag 9.5. Thanks. __________________ This is beautiful. What is this, velvet?

05/04/2016, 10:45 AM	#4
boxxmann Registered Member Join Date: Jun 2007 Posts: 138	So, what am I actually circulating? I probably have about a 4 foot head from the pump to the tank. Is that still adequate? I also have 2 powerheads in the main tank. Does that matter? __________________ This is beautiful. What is this, velvet?

05/04/2016, 11:33 AM	#6
boxxmann Registered Member Join Date: Jun 2007 Posts: 138	Thanks. I hope you are right. I am just a bit afraid because I have had the 9.5 on it for a while and it just crapped out on me this morning. __________________ This is beautiful. What is this, velvet?

05/04/2016, 12:04 PM	#8
boxxmann Registered Member Join Date: Jun 2007 Posts: 138	it actually is a little quieter, but still have the same ol" drain noise __________________ This is beautiful. What is this, velvet?

05/04/2016, 08:48 AM	#2
GimpyFin Registered Member Join Date: Mar 2016 Location: Portland, OR Posts: 2,032	You really only need about 3-5× tank volume for flow per hour on the return, so a mag 7 would be more than adequate at 700 gph.

05/04/2016, 11:18 AM	#5
GimpyFin Registered Member Join Date: Mar 2016 Location: Portland, OR Posts: 2,032	This is just the flow through the sump with the return pump. The flow inside the tank with power heads is separate. I don't know the head loss with a mag 7, but even if you had 50% head loss (Which seems unlikely), you'd still be 350 gph which is between 3-4x tank volume, and perfectly fine.

05/04/2016, 02:53 PM	#9
Potatohead Registered Member Join Date: Apr 2016 Location: Vancouver Posts: 1,596	Before you were running about eight times an hour through your sump, which is fine, but it's a bit on the high side. Now you're more like around 5 which is great.

05/17/2016, 06:20 PM	#10
Romanov Registered Member Join Date: May 2016 Posts: 10	I am running it at 6 times the volume of the tank and seems ok for me